It may be desirable from a driver's standpoint to make an engine run-up to idle speed as soon as possible after the driver requests an engine start. On the other hand, running-up the engine to idle speed as fast as possible may increase engine emissions. Therefore, it may be desirable to provide an engine run-up that produces low emissions while at the same time not extending the run-up time so as to disappoint the driver. However, injecting fuel to an arbitrary engine cylinder or all engine cylinders at the same time may provide somewhat desirable engine starting results at times while producing disappointing engine starting results at other times.
The inventors herein have recognized the above-mentioned disadvantages and have developed a method for starting an engine, comprising: selecting a cylinder of an engine to receive a first port injection of fuel to the engine since engine stop in response to an intake valve of the cylinder being open and a position of the engine allowing end of fuel injection to the cylinder a predetermined number of crankshaft degrees before intake valve closing of the cylinder.
By selecting a cylinder of an engine for a first fuel injection event since engine stop in response to an intake valve of the cylinder being open and a position of the engine allowing fuel injection to the cylinder a predetermined number of crankshaft degrees before intake valve closing of the cylinder, it may be possible to provide the technical result of reducing engine emissions and engine cranking time. For example, fuel may be injected to a cylinder if the fuel injection may be completed early enough to allow a desired amount of evaporated fuel and/or liquid fuel to enter the cylinder. Otherwise, fuel may be injected to a different cylinder after the engine has rotated to a position where the desired amount of evaporated fuel may enter the cylinder.
The present description may provide several advantages. For example, the approach may improve engine starting consistency by reducing the possibility of engine misfire. In addition, the approach may improve engine starting emissions by avoiding arbitrary fueling of engine cylinders. Further, the approach may improve a driver's perception of engine starting.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.